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91.
针对空战目标识别中机型自动识别比较困难的问题,提出了采用航迹特征的智能目标识别方法。利用卷积神经网络(Convolutional Neural Network,CNN)分层学习特征的能力,训练CNN算法模型自动地从航迹数据中学习有用的特征并分类。利用沿海实地采集的15个类别的飞机航迹数据,经一系列数据预处理后作为智能识别算法的训练和测试数据,在验证实验中描述了算法网络的相关配置,对比了CNN与其他分类器的识别结果。实验结果表明,CNN具有很好的识别性能。  相似文献   
92.
Marketers are becoming increasingly reliant on videos to market their products and services. However, there is no standard set of measures of visual information that can be applied to large datasets. This paper proposes two standard measures that can be automatically obtained from videos: visual variation and video content. The paper tests the measures on crowdfunding videos from a leading online crowdfunding website, and shows that the proposed measures have explanatory power on the funding outcomes of the projects. These measures can be effectively implemented and used for large datasets. Further, researchers can apply these measures to other sets of visual information, and marketers could use the research to guide their video design and improve their video marketing effectiveness.  相似文献   
93.
Corporate social responsibility (CSR) has attracted wider research interests over recent decades. While some studies have examined the impact of CSR activities on firm competitive advantage (CA), the findings so far remain contradictory. Moreover, the role of export orientation, firm strategy, and structure on the association between CSR and CA has not been explicitly examined. Thus, the purpose of this study is to examine the moderating role of export orientation, firm strategy, structure, and firm size on the association between CSR and CA. Using a sample of 179 responses from management staff in organizations across five sectors in a developing country context of Ghana, the study found positive effects of CSR on CA. The study contributes to the resource‐based view (RBV) scholarship by confirming the important complementary effect of export orientation and organizational structure as important resources and capabilities on the CSR–competitiveness relationship. However, no evidence of a moderating effect of firm strategy, or firm size on the CSR–CA relationship was found. These findings are instructive, impactful, and enrich the existing literature on CSR and strategy. Implications for theory and practice are also discussed.  相似文献   
94.
The extant literature on behavioral corporate finance has explored the effects of overconfidence on investment–cash flow sensitivity (ICS) to explain overinvestment, yet it has overlooked the asymmetric behavior of investments in relation to changes in cash flow levels. This study examines whether investments behave asymmetrically responding to changes in cash flows and, if so, how managerial overconfidence affects asymmetric ICS. Using a sample of KOSPI and KOSDAQ firms in Korea, we find the incidence of downwardly sticky ICS in unconstrained firms. We then find that overconfident managers encourage ICS to be stickier than their rational peers do in unconstrained firms. Finally, we find that managerial overconfidence intensified by self-attribution bias induces ICS to get even stickier, suggesting more explicit evidence of corporate investment distortions. The results of alternative tests using the asymmetric models of Homburg and Nasev (2008) are qualitatively consistent with prior results. Overall, our findings imply a higher incidence of excessive investment commitments driven by overconfident managers.  相似文献   
95.
吕波  王辉  何悦  周仲鸿 《科技和产业》2021,21(10):252-259
探究黑龙江旅游网络关注度时空演变特征对黑龙江旅游业良性发展具有重要意义.利用百度指数获取2011—2018年全国和分地区黑龙江旅游网络关注度逐日搜索指数数据.从时间分布、空间分布、时空集聚3个方面研究其演变特征.研究表明:2011—2018年全国黑龙江旅游网络关注度年际变化总体呈现上升趋势,月际变化呈"W"形;2011—2018年31个省区市黑龙江旅游网络关注度空间差异较大、季节性影响显著;东部地区黑龙江旅游网络关注度偏高,西部地区黑龙江旅游网络关注度的季节差异最明显;东部地区内的黑龙江旅游网络关注度差异性最小,西部地区内差异性最大;黑龙江旅游网络关注度具有正空间自相关,部分东部、中部地区表现为高高集聚,多数西部地区表现为低低集聚.  相似文献   
96.
[目的]通过对山西省乡村休闲旅游地的空间分布特征及影响因素进行研究,旨在为山西省的乡村旅游发展提供合理的参考建议。[方法]选取山西省213处国家级和省级乡村旅游示范点为研究对象,运用最临近点指数对其空间分布类型进行判别,并运用地理集中指数和地理联系率对其分布均衡程度和地理联系程度进行考量,通过核密度图进一步分析其空间分布指向,在此基础上对影响因素进行分析。[结果]山西省乡村休闲旅游地空间分布呈集聚分布的特点,且与经济规模和人口密度在空间上的均衡、配合程度较高。[结论](1)山西省乡村休闲旅游地包括以太原和晋中为主的中部密集区和以临汾、运城、晋城为主的南部密集区,且都以各地级市为中心向周边扩展,大多数示范点分布于城郊地区; (2)经济发展、人口密度、资源禀赋、区位因素和社会因素是影响山西省乡村休闲旅游地分布的主要因素,其中农业科技类、农事体验类和特色村镇类多分布于经济和人口密度较高的地区。  相似文献   
97.
Islamic equity portfolios work with a smaller investment universe given the filtering of non-Shari’ah compliant stocks. It has been theoretically argued that this culminates in suboptimal portfolio diversification, which in turn adversely affects risk-adjusted returns. We offer empirical evidence that such a conceived portfolio diversification “penalty” is far from a foregone conclusion, at least empirically. Our results tend to indicate that Islamic portfolios are not invariably handicapped in terms of portfolio diversification. We also explored dimensions that may account for differences in the relative investment performance between Islamic and conventional portfolios, such as portfolio constraints, short selling and market conditions. We believe this paper is among the first to apply substantial empirical analysis specifically with respect to the portfolio diversification perspective on Islamic equity investments.  相似文献   
98.
The creation of the Asian Infrastructure Investment Bank (AIIB)was welcomed by the World Bank but opposed by the Obamaadministration. The paper explains China’s positive relationshipwith the Bank and the Organization for Economic Cooperation andDevelopment (OECD) in terms of the mission of the Bank, sharedby the OECD, to develop and deepen the global economy. The AIIBand the related Belt and Road initiative promise to do this throughinvestment in infrastructure and connectivity in and around thepoorly integrated Eurasian landmass. But while the current Chineseleadership has supported an inclusive global economy based uponfree trade and supported by multilateral institutions, China’s controlof resources outside the multilateral framework and adherence topractices that challenge liberal principles prompt suspicions thatthese commitments are either disingenuous or anyway subjectto reversal. In itself, therefore, the AIIB provides no conclusiveevidence either way on China’s future course.  相似文献   
99.
Disparity in the level of digitalization is a crucial driver of economic inequality in an economy. Although a pocket of its population is still bereft of the benefits of digitalization, India currently has the second highest number of internet subscribers in the world despite the nation's late adoption of digital technology. An accurate assessment of the current state of digitalization in the country is required for devising effective initiatives towards building a Digital India and bridging the nation's internal digital divide. Considering 17 major Indian states and 21 variables for 10 years, we constructed a composite index of digitalization with the help of Principal Component Method (PCM). This paper identifies factors responsible for the digitalization divide across states. In the second part of the analysis, the study confirms, with the help of club convergence test, the absence of overall convergence towards digitalization and the existence of the non-convergent group. This paper also shows that the non-convergent group of states are at the bottom of the ranking table which indicates the need for greater attention to initiatives to bridge the digital divide.  相似文献   
100.
Over 1994–2010, adult dietary quality in the United States increased by 10 percent. We find a shift in consumption between at-home and away-from-home food played a relatively minor role as compared to changes in demographics and educational attainment. The two largest contributors we identify include an increased usage of nutritional information and a shift away from relying heavily on price, taste, storability and ease of preparation when shopping for food. Our findings suggest nutrition policy discussions could focus on further shifting attitudes/preferences towards healthier diets while allowing consumers to better extract nutrition information when making food choices.  相似文献   
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